Problem: Consider All lowercase Alphabets of the English language. Here we consider each alphabet from a to z to have a certain weight. The weight of the alphabet a is considered to be 1, b to be 2, c to be 3 and so on until z has a weight of 26. In short, the weight of the alphabet a is 1, and the weight of all other alphabets is the weight of its previous alphabet + 1. 

Now, you have been given a String S consisting of lowercase English characters. You need to find the summation of weight of each character in this String.  

For example, Consider the String aba
Here, the first character a has a weight of 1, the second character b has 2 and the third character a again has a weight of 1. So the summation here is equal to :
 1  + 2 + 1 =  4    

Input Format:
The first and only line of input contains the String S. 

Output Format 
Print the required answer on a single line

Constraints
 1 ≤ |S| ≤ 1000    

SAMPLE INPUT
aba

SAMPLE OUTPUT
4

Explanation

Explanation for the Sample has been given in the Problem Statement.

Solution (in PYTHON):

Solution:
def value(a):
		if(a=='a'):
			return 1
		if(a=='b'):
			return 2
		if(a=='c'):
			return 3 
		if(a=='d'):
			return 4
		if(a=='e'):
			return 5
		if(a=='f'):
			return 6
		if(a=='g'):
			return 7
		if(a=='h'):
			return 8
		if(a=='i'):
			return 9
		if(a=='j'):
			return 10
		if(a=='k'):
			return 11
		if(a=='l'):
			return 12
		if(a=='m'):
			return 13
		if(a=='n'):
			return 14
		if(a=='o'):
			return 15
		if(a=='p'):
			return 16
		if(a=='q'):
			return 17
		if(a=='r'):
			return 18
		if(a=='s'):
			return 19
		if(a=='t'):
			return 20
		if(a=='u'):
			return 21
		if(a=='v'):
			return 22
		if(a=='w'):
			return 23
		if(a=='x'):
			return 24
		if(a=='y'):
			return 25
		if(a=='z'):
			return 26
s=raw_input()
count=0
for i in s:
	count+=value(i)
print count